Bag holding device for filling machine



June 9, 1959 F. HOPKINS 2,890,006

BAG HOLDING DEVICE FOR FILLING MACHINE 2 Sheets-Sheet 1 Filed April 25. 1956 INVENTOR.

F. L. HOPKINS BAG HOLDING DEVICE FOR FILLING MACHINE June 9, 1959 Filed April 23, 1956 2 Sheets-Sheet 2 Frank L. Hopkins, Minneapolis, mis Bro. Bag 'Co., St. Louis, Missouri Application April 23, 1956, Serial No. 580,055 6 Claims. (Cl. 248-101) Minn., assignor to Be- Mo., a corporation of My present invention relates generally to improvements in bag filling machines and, more particularly, to bag holding devices for bag filling machines of the type wherein a bag is supported on a filling spout or chute while being filled therefrom.

An important object of my invention is the provision of a bag filling chute or tube which tapers downwardly toward its open lower discharge end whereby bags or like containers may be easily applied thereto by an operator.

Another object of my invention is the provision of novel means for releasably supporting a bag on the downwardly tapering chute whereby, when the filled bag is released, the bag will fall freely fromv the chute.

Another object of my invention is the provision of bag holding means as set forth which is mounted on and carried by the bag loading chute and which requires no other support on the bag filling machine.

Another object of my invention is the provision of bagsupporting mechanism as set forthhaving primary and secondary bag engaging means, the former being operative to engage portions of a bag adjacent its open upper end and support the samein an operative receiving position on the downwardly tapering chute,-. and the latter being operative to engage opposite side edge portions of a'bag to close the free upper end portions thereof at opposite sidesof the chute.

United States Patent 1 A still further object of my invention is; the provision of bag holding mechanism of the above type which is simple and inexpensive to manufacture and install, which is highly 'eflicient in operation, and which is rugged in construction and durable in use.

;The above and still further highly important objects and advantages of'my invention will become apparent from the following detailed specification, appended claims .and attached drawings. Referring to the drawings, which illustrate the invention, and in which like characters indicate-like parts throughout the several views: a

" Fig. l'is a fragmentary view in side elevation of a hopperlike bag loading chute incorporating my invention;

Fig. 2 is a fragmentary view corresponding to the intermediate portion of Fig. l but showing a different position of some of the parts; I

Fig. 3 is a fragmentary the right to the left with respect Fig. 4 is a view partly in bottom plan and partly in section taken substantially on the line 4--4 of Fig. 1.

' Referring with greater detail to the drawings, the .numeral 1 indicates in its entirety a hopper-like portion of a conventional bag filling machineincluding a relatively large section 2 to which is secured a relatively small tubular discharge chute 3. The portion 1 may be assumed to be mounted on the frameworkiofa machine for filling bags or like containers with granular or powdered bulk material, such machines being well-known and extensively used in the packaging art. The enlarged secview in elevation as seen from to Fig.1; and

vices such as weighing buckets the same being also commonly used in packaging machinery. Inasmuch as the instant invention may be, and is shown as being, operated independently of the remainder of the bag filling mechanism, further showing and description of the bag filling mechanism is not deemed necessary. Hence, for the sake of brevity, such showing and description has been omitted. A peripheral flange 5 at the joinder between the section 2 and the chute or tube 3 supports a generally annular mounting plate 6 to which the chute 3 is welded or otherwise rigidly secured. It will be noted that the tube 3 tapers downwardly toward its open discharge end 7, and that the same is provided with a pair of horizontally disposed laterally outwardly extending stop flanges or plates 8 in downwardly spaced relation to the flange 5 to limit upward movement of an open bag A positioned on the tube 3 to receive material therefrom. The mounting plate 6 is secured to the peripheral flange 5 by nut-equipped bolts or the like 9, see Figs. -1 and 3. It will further be noted that the stopflanges' 8 extend a suflicient distance outwardly from opposite side portions of the chute 3 to engage the upper edges of bags of various widths larger than the diameter necessary to receive the tube 3, so that bags of various sizes and capacities may be filled without the necessity of substituting parts of different sizes for those in use on the machine when it is desired to use a different sized bag. The downward taper of thetube 3 permits the operator to more easily place a bag thereover than if the sides of the tube 3 were parallel. It has been found in practice that a considerable amount of time has been saved in placing bags to be filled on the tube 3 because of the downward taper thereof. Furthermore, the vdownward taper of the tube 3 permits a filled bag to be more easily released from the tube 3 than has been heretofore possible, particularly when bags are used which fit snugly around the discharge chute.

Notwithstanding the several advantages of the downwardly tapered discharge tube 3, the question of mechanically supporting a bag thereon has created a definite problem which I have solved in a manner and by mechanism now tobe described. A pair of rockshafts 10 and 11 are journaled in spaced bearings 12 which depend from the mounting plate 6 at opposite side edges thereof. The rockshafts 10 and 11 are horizontally disposed in parallel relationship laterally outwardly of opposite side portions of the discharge tube 3, and extend generally in the directions of the opposed stop flanges 8. A pair of bag supporting arms 13 and 14 are rigidly secured, each to a respective shaft 10 and 11 intermediate the bearings 12, by means of setscrews or the like 15. The bag supporting arms 13 and 14 depend from their respective shafts 10 and 11, the lower ends 16 thereof being disposed below the plane of the stop flanges8 and defining or the like not shown,

recesses in which are mounted resilient bag engaging pads 17 which are preferably made from rubber or the like. Rocking movement of each of the shafts 10 and tion z'underlies the discharge ends. 4 of dispensing de- 1 .111 in a given direction causes the resilient pads 17 to engage opposite outer surface portions of the bag A "adjacent the open upper end thereof to frictionally hold the same against underlying surface portions of the downwardly tapering tube 3, even when the bag or container A is filled with material dispensed by the overlying discharge' portions 4 of the bag filling mechanism, not shown. Obviously, when the rockshafts 10 and 11 'are rotated in the opposite direction to position the arms as shown in Fig. 2, the bag A is released and drops under the action of gravity to a suitable receiving plat- .form or the like, not shown.

.' The rockshafts 10 and 11 are held against axial movement by crank arms or the like 18 pinned or otherwise rigidly secured thereto at their inner ends adjacent the bearings 12, see Figs. 3 and 4. The rockshaft has an end portion 19 upon which is mounted a crank 20 comprising a bifurcated upper crank section 21 and a lower bifurcated crank section 22. The crank 20 is keyed or otherwise secured to the extended end 19 of the shaft 10 for common movements therewith, as indicated at 23, see Figs. 1 and 2. The rockshaft 11 is likewise provided with an end portion 24 that extends axially in thesame direction as the end portion 19 of the shaft 10. A crank arm 25 is welded or otherwise rigidly secured to the extended end portion 24 and extends in a direction generally upwardly therefrom, as does the bifurcated crank section 21 of the crank 20 from its respective shaft end portion 19. A fluid pressure cylinder 26 is disposed between the legs of the bifurcated crank section 21' and is pivotally connected intermediate its ends to the upper end of the bifurcated crank section 21, as indicated at 27. A piston plunger 28 is carried by the cylinder 26 for extending and retracting movements with respect thereto, and is pivotally connected at its outer end to the upper end of the crank arm 25 as indicated at 29. As shown, the outer end of the piston plunger rod 28 is bifurcated, the upper end of the crank arm 25 being received within the bifurcated end thereof, the pivotal connection 29 being in the nature of a connecting pin. A rubber-like bellows 30 encompasses the plunger rod 28 and is clamped at one end to theouter end portion of the plunger rod 28 by a suitable clamping band 31, and at its other end to the adjacent end of the cylinder 26 by a similar clamp ing'band 32. The bellows 31 protects the plunger rod 28 from abrasive dust and the like and thus lengthens the effective life of the interengaging portions of the cylinder 26 and plunger 28.

Inasmuch as the cylinder 26 is operatively coupled to the crank 20 and the plunger rod 28 is similarly coupled to the crank arm 25, introduction of fluid under pressure to one end of the cylinder 26 will cause the plunger rod 28 to move axially outwardly with respect thereto and impart rocking movements to the rockshafts 10 and 11 in directions to move their respective bag engaging arms 13 and 14 toward engagement of their respective pads 17 with opposed portions of a bag A manually positioned on the discharge chute section- 3. On the other hand, when fluid under pressure is introduced to the opposite end of the cylinder 26, the plunger rod 28 will be caused to be retracted and the bag engaging arms 13 and 1:4 moved to their bag releasing inoperative positions of Fig. 2.

The arrangement above described is such that, due to inequalities in friction between the several cooperating parts, or due to unequal inertia, one of the bag engaging arms 13 or 14 is likely to move into its operative bag engaging position of Figs. 1 and 4 at a diflerent time than the other thereof. For the purpose of causing the rockshafts 10- and 1 1 to operate simultaneously, to cause the opposite sides of the bag to be gripped by the pads 17 or released therefrom at the same time, I provide a rigid motion transmitting link 33 having a bifurcated end portion 34 which is pivotally connectedto the crank arm 25intermediate the end portion 24 ofthe rockshaft 11, as indicated at 35. The opposite end -0f the link 33 is axially slidably received in a slide block 36 that is pivotally connected by means of trunnions or the like 37 within the bifurcated crank section 22 of the crank 20 on an axis parallel to the axis of the adjacent rockshaft 10. A pair of cushioning elements in the nature of coil compression springs 38 encompass the adjacent end portion of the link 33, one each of the springs 38 being interposed between an opposite side of the slide block 36 and one of'a pair of abutment elements or nuts 39 screw-threaded on the adjacent end portion of' the link 33. Inasmuch as the bifurcated end 34' of the link-33-is-connected to the crank arm 25-generally above the axisof-the rock shaft- 11 and the opposite end thereof is connected to the bifurcated crank section 22 generally below the axis of the rock shaft 10, it should be obvious that movement imparted by the cylinder 26 and piston plunger 28 to the crank arm 25 in one direction will cause like movement to be imparted to the crank 20 and rock shaft 10 in the opposite direction. With this arrangement, both bag engaging arms 13 and 14 are caused to move simultaneously into and out of their bag supporting positions. The cushioning springs 38 and the resiliency of the pads 17 is suflicient to prevent damage to the engaged side wall portions of the downwardly tapering discharge chute section 3 when the arms 13 and 14 are moved to their operative bag supporting positions without detracting from the bag supporting ability thereof.

In Fig. 1, I show a preferred arrangement (for controlling and operating my novel bag holding means. The opposite ends of the fluid pressure cylinder 26 are adapted to be selectively connected to. a source of fluid, such as air, under pressure by means of conduits 40 and 41 and a conventional 4-way valve 42. In Fig. 1 a source of pressure is shown. as comprising a conventional pump 43. The valve 42 is preferably operated by a conventional solenoid 44 suitably mounted on the frame. structure and interposed in an electrical circuit comprising a pair of leads 45 and 46 which may be assumed to be connected to a source of electrical potential, not shown. A control switch 47 is shown as being interposed in the lead 46 for controlling operation of the solenoid 44 and the valve 42. With the valve 42 positioned as shown in Fig. 1, air under pressure is introduced from the pump 43 through the conduit 40 to cause the bag engaging arms 13 and 14 to be moved simultaneously to their operative bag engaging positions of Figs. 1 and 4'. This is caused by manual closing of the switch 47 by the operator while said operator holds a bag in position on the discharge chute section 3. Obviously, as soon as the bag A is supported by engagement of the pads 17 therewith, the operator may then release the bag and operate the necessary controls, not shown, to cause the same to be filled. Thereafter, when the switch 47 is opened, the solenoid 44 will cause the valve 42 to be positioned in a manner to permit air under pressure to be introduced to the opposite end of the cylinder 26 through the conduit 41. This position of the valve 42 permits fluid from said one end of the cylinder 26 t0 escape to atmosphere through the conduit' 40- andthe valve 42 and pressure at said opposite end of the cylinder will cause the piston plunger 28' to be retracted'and the bag supporting arms 13 and 14 to be simultaneously moved to their inoperative bag releasing-positions of Fig. 2.

Inasmuch as it is desirable to utilize the above described device in the filling of bags of various sizes, it has been found necessary to provide means for-causing relatively wide bags to snugly engage the outer surface of the chute, and to close the open upper ends of said relatively wide bags laterally outwardly of the tube 3 to prevent material in the powdery form from escaping upwardly and-outwardlytherefrom when the material is dumped into the bag A. For this purpose I provide pairs of cooperating jaw-acting arms 48 that are pivotally secured at their upper ends to hearing blocks or the like 49- at opposite sides of the tube 3 and on axes parallel tothe axes of the rockshafts 10 and 11. At their lower ends, the jaw-acting arms are provided with rubher-like bagengaging pads 50. Each of the jaw-acting arms 48 i's connected to an adjacent one ofthe crank arms 18 by a longitudinally adjustable rigid link 51 Each of the'links 51 is pivotally secured to the intermediate portion of its respective jaw-acting arm 48' as indicated at 52, and at its outer end to the outer end ofits respective crank arm 18 asindicated at 53. With this arrangement, when each bag supporting arm 13*and 1-4' moved to its operative-bag engaging position; the

jaw-acting arms 48 of eachpair thereof are simultaneously moved toward each otherand into engagement with an adjacent side edge portion of the bag A which, in the event that the bag is of substantially greater diameter than the tube 3, will cause the bag to snugly engage the outer surface ofthe tube 3 and close any opening which might otherwise be found outwardly of the tube 3. Then, when powdered or-granular material containing particles sufiiciently light in weight to easily float in the air, is discharged into the bag A, such particles are prevented from escape upwardly from the bag exterior of the chute. e

The bag A is shown as being in type bag of sufliciently greater diameter than that of the tube 3 so that, when the bag is =applied'to the tube and the holding mechanism rendered operative, the gusset portions of the bag A are gripped by the pads 50 and held in a folded position adjacent the outer surface of the chute section 3. Obviously any suitable bag, not

the nature of a gussetnecessarily a gusset-type bag may be closed outwardly of i the chute and caused to snugly engage the same by the above-described mechanism.

It will be appreciated that the cushioning springs 38 will yield sufliciently, in the event that an operators fingers or hands are caught between the bag holding mechanism and the tube 3, to effectively prevent undue injury to the operator. Although I have shown and described manually controlled means causing the bag holders to engage and hold a bag on the tapered tube 3, and to release the bag when filled, it will be appreciated that other well-known control devices may be utilized, if desired, to cause a bag to be automatically filled and automatically released from the tube 3 when the filling operation is completed.

My novel device has been thoroughly tested and found to be completely satisfactory for supporting a bag on a downwardly tapering discharge chute or tube without causing the bag to be torn or otherwise damaged and without permitting the bag to slip. The same mechanism operates with equal facility on bags A made from paper, cloth, or synthetic resins, and provides a relatively lightweight, simple and inexpensive arrangement for accomplishing the objectives set forth.

While I have shown and described a commercial embodiment of my novel bag supporting mechanism, it will be understood that the same is capable of modification, and that modification may be made without departure from the spirit and scope of the invention as defined in the claims.

What I claim is:

1. In a bag filling machine, a downwardly directed chute adapted to have its lower discharge end portion received in a bag to be filled, said chute having downwardly converging opposite side wall portions, a pair of bag supporting arms, bag engaging elements on said arms engaging adjacent opposite downwardly converging sides of the lower end portion of said chute, means mounting said arms for common movements bet-ween operative positions, wherein said bag engaging elements engage opposed outer wall surface portions of a bag adjacent the open upper end thereof and frictionally hold said bag wall portions against the underlying downwardly converging outer surface portions of said chute contained within the bag, and inoperative bag releasing positions wherein said bag engaging elements are laterally outwardly spaced therefrom, an extensible and retractable member operatively connected to each of said arms for imparting movement to one of said arms relative to the other thereof, and motion transmitting linkage connecting said arms for common movements in opposite directions with respect to each other, whereby movement of one arm in one direction will cause equal movement to be imparted simultaneously to the other arm in the opposite direction relative to said chute.

2. In a bag filling machine, a downwardly tapering delivery .chute having a dischargeopening' atits lower :endand adapted to be received in .a bag to be filled, a pair of'bag supporting rock arms, bag engaging elements on the free ends. of said rock arms, means mounting said arms on said chute for rocking movements between operative positions, wherein said bag engaging elements engage opposed outer wall surface portions of a bag adjacent the open upper end thereof and frictionally hold said bag wall'portions against downwardly converging opposite side portions of the downwardly tapering chute contained within the bag, and inoperative bag releasing positions wherein said bag engaging elements are laterally outwardly spaced therefrom, an extensible and retractable member operatively connected to. each of said arms for imparting movement to one of said arms relative to the other thereof, and motion transmitting linkage connecting said arms for common movements in opposite directions with respect to each other, whereby movement of one arm in one directiontwill cause equal movement to be imparted simultaneously to the other arm in the opposite direction.

3. In a bag filling machine, a downwardly tapering delivery chute having a discharge opening at its lower end and adapted to be received in a bag to be filled, a pair of horizontally disposed parallel rock shafts journaled one each at an opposite side of said chute in upwardly spaced relation to the lower discharge end thereof, a pair of bag supporting arms rigidly secured one each to a different one of said shafts and depending therefrom, bag engaging pads on the lower ends of said arms, means including an extensible and retractable member operatively connected to said shafts for imparting rocking movements to one of said shafts relative to the other thereof and to said chute, and motion transmitting linkage operatively connecting said shafts together for common movements in opposite directions, whereby said arms are simultaneously moved between operative positions wherein said pads engage opposed outer wall surface portions of a bag adjacent the open upper end thereof and frictionally hold said bag wall portions against the underlying downwardly converging outer surface portions of said chute contained within the bag, and inoperative bag releasing positions wherein said bag engaging pads are laterally outwardly spaced therefrom.

4. In a bag filling machine, a downwardly tapering delivery chute having a discharge opening at its lower end and adapted to be received in a bag to be filled, a pair of rock shafts journaled on parallel horizontal axes at opposite sides of said chute in upwardly spaced relation to the bag receiving lower end portion thereof, a pair of opposed bag supporting arms one each rigidly mounted at its upper end to and depending from a different one of said shafts for common rocking movements therewith, opposed resilient bag engaging pads on the lower free end portions of said arms and movable with said arms between operative positions, wherein said pads engage opposite outer wall surface portions of said bag adjacent the open upper end thereof and clamp the same against the underlying downwardly tapering side wall portions of said chute, and inoperative bag releasing positions outwardly spaced therefrom, a crank arm mounted fast on one end of one of said rockshafts, a second crank mounted on the adjacent end of the other of said shafts and comprising a pair of cooperating crank sections which extend radially outwardly from said other shaft substantially in opposite directions, a fluid pressure cylinder and a cooperating piston plunger mounted in said cylinder for relative extending and retracting movements, said cylinder being pivotally mounted on and carried by one of said crank sections, the outer end of said piston plunger being pivotally connected to said crank arm, a rigid link pivotally connected at one end to said crank arm, and means connecting the other end of said link to the other one of said crank sections, said link transmitting plunger imparted movement of 7 saidrcrank arm to said second crank tocause simultaneous movementrof'said bag supporting arms toward their operative or inoperative positions.

5. The structure defined in claim 4 in which said last mentioned means comprises a slide block pivotally secured to its respective crank section and longitudinally slidably receiving the adjacent endportion of said link, and cushioning elements yieldingly biasing said link against sliding movements in opposite directions relative to. said slide block.

6. In a bag filling machine, a downwardly directed chutevadapted to have its lower discharge end portion received in a bag to 'be filled, said chute having downwardly converging opposite side wall portions, a pair of bag supporting arms, bag engaging elements on said arms engaging opposite sides of the lower end portion of said chute, means mounting said arms for common movements between operative positions, wherein said bag engaging elements engage opposed outer wall surface portions of a bag .adjacent .the open upper end thereof and frictionally hold said bag wall portions against-the underlying downwardly converging outer surface portions of said chute contained within the bag, and inoperative bag releasing positions wherein said bag engaging elements are laterally outwardly spaced there r 8 from, cooperating bag engaging jaws disposed at opposite sides of said chute in spaced relation to said bag engaging elements and connected to said arm mounting means for common-movements with said arms and toward and away from engagement with opposite side edge portions of said bag to close the open upper end portions thereoflaterally outwardly of said chute to effectively reduce the size of the bag opening to correspond with the engaged portion of said chute, mechanism operatively connected to each of said arms for imparting one thereof relative to the other thereof, and motion transmitting linkage connecting said arms for common movements in opposite directions with respect to each other, whereby movement of one ofsaid arms in one direction will cause equal movement to be imparted simultaneously to the other arm in the opposite direction relative to said chute.

References Cited in the file of this patent UNITED STATES PATENTS 669,607 Wickman et a1. Mar. 12, 1901 2,039,561 Sharkey .L May 5, 1936 2,100,501 Bennett Nov. 30, 1937 2,332,002 Neuman Oct. 19, 1943 2,671,585 Kindseth Mar. 9, 1954 

